Grinding-machine.



' WITNESSES.

J. A. CRAIG.

GRINDING MACHINE.

APBLIOATIOII FILED APR}, 1914.

Patented Jan. 5, 1915.

2 SHBBTSSHEET 1.

J. A. CRAIG.

GRINDING MACHINE.

APPLICATION FILED 1mm, 1914.

2 T E E H 4 s T E E H S 2 A TTOZPNE) JES AJRCHIBALD CRAIG, 0F TORONTO, ONTARIO, CANADA, ASSIGNOR 0F ONE-THIRD T0 HOLT-EN W. RICH, OF BUFFALO, NEW YORK, AND ONE-THIRD TOCHARLES JAMES RICH, 0E CATTARAUGUS, NEW YORK.

GRINDING-MACHINE.

nieaiei.

Specification of Letters lt'atent.

Application filed April 2, 191 1. Serial No. 828,996.

To all whom it may concern Be it known that I, JAMES ARGHIBALD Cram, a citizen of the United States of America, residing at Toronto, Province of Qntario, and Dominion of Canada, have 1nvented certain new and useful Imgrovements in Grinding-Machines, of which the following is a full, clear, and exact description.

My invention relates generally to grain grinding machines, and more particularly to that type of machine wherein a stationary grinding head is mounted ad acent to, and axially movable to and from, a rotatable grinding head. As is well known to those skilled in the art, many grinding machines of this: type have been so constructed that when they need repairs or the replacing of a grinding plate, in most cases they cannot be taken apart by the ordinary mechanic, but it has been necessary to send them to the factory, thus adding greatly t9 the expense of repairs as well as necessltating a great loss of time.

The principal object of my invention has been to provide a device which may be easily assembled and one which can be eas ly taken apart by any mechanic familiar with machinery.

Another object has been to increase the effective grinding area of the grinding plates or rings of the machine.

Another object has been to provide a device having grinding plates or rings so arranged that very coarse materlal may be ground to powder in one grlndmg opera tion.

The objects and advantages above enumerated, and also other advantages which will be apparent to those skilled in the art, have been accomplished by the device shown in the accompanying drawings. 1

In the drawings, forming part of this specification, like charactersof reference indicate like parts throughout the several views of which:

Figure 1 is a side elevation of my device and shows part thereof in section, said sectionbeing taken on the vertical center line. Fig. 2 is an end elevation of my device.

Fig. 3 is a fragmentary side elevation and :hows part of the adjusting means in sec} 5 is the base of my device which supports all of the working parts of the machine.

6 is the rotatable grinding head, and 7 the stationary grinding head. The rotatable head 6 is suitably secured to the inner end of the main shaft 8. This shaft is mounted preferably in ball bearings of any suitable well known type, which are supported by the bearing standards 9 and 10, preferably made integral with the base 5. Each of the bearing standards 9 and 10 is provided with a suitable bearing cap 11 secured to the standard by well known means. The bearing standards 9 and 10 are each provided with a cap or plate 12 and 13, respectively, which are suitably secured to said bearing standards and their caps and serves to close the bearing and prevent dust from entering the same, and also serve to retain the lubricating medium. The shaft 8 is provided with a suitable drive pulley 14 by which the rotatable head is driven.

The stationary grinding head 7 is provided with a hub 15, which is set into a recess formed in the supporting member 16 and is secured thereto by suitable bolts 44. This supporting member is slidably ar ranged on the upper surface of the base 5 and is provided with a plurality of longitudinal ribs 17, which engage with co-acting grooves formed in the upper surface of the base, and which guide the supporting member as it moves back and forth when the stationary head 7 is being adjusted. Suitable bolts 18 are provided at each side of the supportin member 16. These bolts pass throng slots 19 provided in the supporting member and are each provided with an integral washer 20 which bears on the upper surface of the flange of the supporting member. The bolts 18 are screwed down and adjusted so that the supporting member may be moved back and forth by its adjusting means without altering the bolts. When these bolts are adjusted at lock-bar 21 is placed over the flat sides of the bolts 18, thereby holding them in position.

. conveyer trough.

The supporting member 16 and the hub 15 of the 'stationar grinding head are each rovided with a arge central aperture, thus orming a trough in which is arranged a conveyer 22. The conveyershaft 42 is made separate from the main shaft 8 and is screwthreaded at its inner end to the end of the main shaft and thereby rotates with it. A plate 23 is secured to the outer end of the supporting member and serves to close the outer end of the conveyer trough. A hopper 24 issecured at the top of the supporting member 16 and communicates with an opening 25 in the supporting member, whereby the grain or other material being ground may be carried to the The grinding heads 6 and 7 of my device are each preferably provided with a finishing grinding plate or ring 26, and a roughing or grinding ring 27. The finishing rings 26 are each preferably formed of a number of sections and are disposed near the outer circumference of the grinding heads. The roughing or grindin ring 27 is preferably made in one piece an is disposed within the finishing plate or ring 26. As is well known, the grinding plates or rings in this class of machinery are made from hard steel and are usually secured to the grinding heads by means of T bolts passing through the plates and having their heads disposed in slots formed in the rinding surface of the plate. This not only ecreases the grinding area of the plates, but also provides pockets for the lodgment of foreign substances. When forming my grinding plates,-I preferably cast a steel nut 28 in the material forming the plate and below the grinding surface of the same, thus leaving the working surface unaffected by the fastening means and thereby increasing the grinding area, and also overcoming the ob ections just above enumerated. The sections of the finishing ring 26 and the roughing ring 27 are secured to the heads 6 and 7, preferably by means of bolts 29, which pass through the heads and into the screw-threaded nuts 28 molded in the grinding plates. If desired, the nuts 28 may be omitted and the thread cast into the grinding plates, or the same may be drilled and afterward tapped in a well known manner before the plates are hardened for use.

The rear side of each of the grinding plates is preferably provided with a plurality of annular grooves 43, thus reducing the bearing area and making it easier to finish the surface. Between the rear side of the roughing rings 27 and the heads 6 and 7, I

rovide a plurality of thin spacing disks 30. Vhen it is desired to grind a coarse material to a fine powder in one operation, one or more of these disks may be easily removed from behind the roughing ring and thus increase the space between the two co-acting roughing rings, thereby crushing the coarse material previous to its entrance between the finishing grinding plates 26. It is obvious that the spacing rin s 30 may be placed behind the outer grin ing plate 26, as well as behind the roughin rings 27, and the same results accomplished.

31 and 32 represent the two halves of a two-part casing, which is arranged about the grinding-heads. These casing parts are secured together at the top by means of a bolt 33, and to the base plate 5 by means of bolts 34. Each casing part is preferably provided with suitable handles 35 by which it may be conveniently removed.

Referring now to Figs. 2 and 3 where the stationary head adjusting means are shown in detail, 36 are screw-threaded studs, which have their inner ends suitably secured to the casing parts 31 and 32. These studs extend rearwardly and pass between slotted lugs 37 provided on the supporting member 16. 38 are adjusting hand wheels, and 39 lock-nuts screw-threaded to the outer end of the studs 36. Adjusting nuts 40 are also provided on the studs between the lugs 37 and the casing parts. Each of the studs 36 has a spring 41 disposed at each side of the lug 37. The inner springs 41 have their inner ends bearing against the adjusting nuts 40, and the outer springs 41 have their outer ends bearing against the adjustin hand wheels 38. By this means the stationary head is yieldably held in o erative position so that when some hard fbreign substance enters between the grinding surfaces of the devi e, the stationary head will move against the tension of the springs, thereby increasing the space between the co-acting grinding surfaces and permit such foreign substance to pass between the heads without injuring the grinding plates, after which the stationary head w1ll return to its normal position. Thus, it will be seen that by adjusting the lock-nuts 40and 38, the distance between the rotating and stationary heads may be varied. When the hand wheels 38 have been adjusted, the lock-nuts 39 are screwed up tightly against the same and securely hold them in their adjusted position.

It will clearly be seen that when it is desired to repair or replace the grinding plates in my devlce, the adjusting means are first loosened and then the casing parts 31 and 32 are, together with the adjusting means, removed. The conveyor 22 is next unscrewed from its engagement with the shaft, after the head 23 has been removed. The supporting member 16 may now be moved back upon the base 5, whereupon the grinding heads will be easily accessible. The rotatable grinding head and main shaft 8 may be easily and quickly removed, if desired, by simply detachingplates 12 and 13 and removing the caps 11.

maaaea tilt Having thus described my invention, what I claim 1s:

1. A grain grinding machine comprising a rotatable head, a non-rotatable head, a grinding plate detachably secured to each of said heads, and a plurality of spacing disks detachably mounted between each of said grinding plates and said heads, whereby the distance between the grinding surfaces may be changed as desired.

2. A grain grinding machine comprising a rotatable head, a non-rotatable head, an outer grinding plate detachably secured to each of said heads, an inner grinding plate detachably secured to each of said heads, a

plurality of spacing disks detachably mounted between each of said inner grinding plates and said heads, whereby the relative distances between the grinding surfaces may be changed as desired.

3. A ain grinding machine comprising a rotata 1e head, a non-rotatable head, an outer and an inner grindin plate mounted on each of said heads, sai grinding plate being provided with unbroken grindin faces and screw-threaded means integra ,with said blades for detachably securing them to said heads, a plurality of spacin disks detachably mounted between each '0 said inner grinding plates and said heads, whereby the relative distances between the grinding surfaces may be changed as desired.

In testimony whereof, l[ have hereunto signed my name-in the presence of two subscribing witnesses.

JES AlEtCll-IIBALD CRAIG.

Witnesses:

J. WM. ELLIS, WALTER H. lt 

